There is no official UK government medical cannabis card. Access is always...

https://iris-wiki.win/index.php/Can_a_GP_Prescribe_Medical_Cannabis_in_the_UK%3F_A_Guide_to_the_Access_Pathway

There is no official UK government medical cannabis card. Access is always prescription-first via a specialist consultation and your medical records. You may purchase an optional private patient card solely as proof of your lawful prescription.